贵州省NDVI时空变化及其对温度和降水变化的响应
任荣仪, 贺中华, 梁 虹, 夏传花, 张 浪, 杨铭珂

(贵州师范大学 地理与环境科学学院, 贵阳 550025)

NDVI; 稳定性; 可持续性; 温度; 降水; 贵州省

Spatiotemporal Variation of NDVI and Its Response to Changes in Temperature and Precipitation in Guizhou Province

(School of Geographic and Environmental Science, Guizhou Normal University, Guiyang 550025, China)

NDVI; stability; sustainability; temperature; precipitation; Guizhou Province

备注

为了探究植被NDVI变化特征及其对温度和降水变化的响应,以贵州省为例,基于2000—2018年MODIS NDVI数据和温度、降水数据,采用距平分析、滑动平均、M-K检验、一元线性回归趋势分析、Pearson相关分析,偏相关分析、复相关分析及F检验进行显著性检验,定量分析了贵州省不同地貌类型下温度和降水对植被NDVI的影响。结果 表明:(1)2000—2018年贵州省年均NDVI在空间分布上呈现出西北低东南高的格局; NDVI在2007年和2010年发生突变,并于2013年进入快速增长时期; 其变化趋势呈现极显著增加的区域面积占比较大的是岩溶峡谷区和断陷盆地区,非喀斯特区较小;(2)NDVI以中高稳定和中等稳定为主,变异系数空间上存在着西北高于东南的格局; 非喀斯特地貌稳定性最高,岩溶峡谷地貌的稳定性较差;(3)Hurst指数介于0.07～0.99,高值主要分布在贵州省西部地区,低值主要分布在东部地区,岩溶峡谷区和断陷盆地区呈现正向持续区域面积均超过对应地貌类型面积的1/2,其余地貌区以反向持续的区域面积比相对较大;(4)贵州省年均温度在空间上呈现西部地区低南部地区高的格局。以0.260℃/10 a的速率上升,断陷盆地区温度变化是最稳定的,非喀斯特地区和岩溶槽谷区的温度变化差异性较大。贵州省大部分地区降水量比较高,仅研究区西北部略低。年均降水以38.16 mm/10 a的速率上升,除断陷盆地区降水以减少趋势占优势,其他地貌区均呈现不同程度的增加;(5)贵州省NDVI受温度的影响强于降水,断陷盆地区受温度和降水的影响均不显著; 岩溶高原区、岩溶峡谷区和非喀斯特地区受温度的影响高于降水。

In order to explore the characteristics of vegetation NDVI change and its response to temperature and precipitation changes, Guizhou Province was taken as an example, based on the MODIS NDVI data and temperature and precipitation data from 2000 to 2018, anomaly analysis, moving average, M-K test, univariate linear regression trend Analysis, Pearson correlation analysis, partial correlation analysis, complex correlation analysis, and F test for significance test were used to quantitatively analyze the effects of temperature and precipitation on vegetation NDVI under different landform types in Guizhou Province. The results showed that:(1)from 2000 to 2018, the annual average NDVI of Guizhou Province showed a pattern of low northwest and high southeast; the NDVI was abrupt in 2007 and 2010, and entered a period of rapid growth in 2013; the area was relatively large in the karst canyon area and the rift basin area, and the non-karst area is smaller;(2)NDVI was dominated by medium-high stability and medium stability, and there was a spatial pattern which coefficient of variation was higher in northwest than southeast; non-karst topography had the highest stability, and the stability of karst canyon was poor;(3)the Hurst index was between 0.07 and 0.99; the high values mainly distributed in the western part of Guizhou Province, and the low values mainly distributed in the eastern part; the areas of forward direction sustainability were greater than half of the corresponding areas both in the karst canyon area and the rift basin area, the area ratio of the remaining geomorphic areas in the reverse direction was relatively large;(4)the average annual temperature of Guizhou Province presented a spatial pattern that was lower in the western region and higher in the southern region, rising at a rate of 0.260℃/decade; the temperature change in the rift basin area was the most stable, and the temperature changes in the non-karst area and the karst trough area were quite different; the precipitation in most areas of Guizhou was relatively high, only slightly lower in the northwestern part of the study area; the annual average precipitation rose at a rate of 38.16 mm/decade; except for fault depression basins, precipitation tended to decrease, and other geomorphic areas showed the increase with varying degrees;(5)the effect of temperature on NDVI in Guizhou Province was stronger than that of precipitation, and the impacts of temperature and precipitation on NDVI in rift basin areas were not significant; the impact of temperature on NDVI was higher than that of precipitationin karst plateau area, karst canyon area and non-karst area.